#define _CRT_SECURE_NO_WARNINGS 1

#include "SList.h"

//void SLTPrint(SLTNode* phead)
//{
//	assert(phead);
//	SLTNode* pcur = phead;
//	while (pcur)
//	{
//		printf("%d->", pcur->data);
//		pcur = pcur->next;
//	}
//	printf("NULL\n");
//}

SLTNode* SLTBuyNode(SLTDataType x)
{
	SLTNode* newnode = (SLTNode*)malloc(sizeof(SLTNode));
	if (newnode == NULL)
	{
		perror("malloc fail!\n");
		exit(1);
	}
	newnode->data = x;
	newnode->next = NULL;

	return newnode;
}
void SLTPushBack(SLTNode** pphead, SLTDataType x)
{
	assert(pphead);
	SLTNode* newnode = SLTBuyNode(x);
	if (*pphead == NULL)
	{
		*pphead = newnode;
		return;
	}
	SLTNode* ptail = *pphead;
	while (ptail->next != NULL)
	{
		ptail = ptail->next;
	}
	ptail->next = newnode;
}

void SLTPushFront(SLTNode** pphead, SLTDataType x)
{
	assert(pphead);
	SLTNode* newnode = SLTBuyNode(x);

	newnode->next = *pphead;
	*pphead = newnode;
}

void SLTPopBack(SLTNode** pphead)
{
	assert(pphead);
	assert(*pphead);

	if ((*pphead)->next == NULL)
	{
		free(*pphead);
		*pphead = NULL;
		return;
	}

	SLTNode* ptail = *pphead;
	SLTNode* prev = NULL;
	while (ptail->next)
	{
		prev = ptail;
		ptail = ptail->next;
	}
	prev->next = NULL;
	free(ptail);
	ptail = NULL;
}

void SLTPopFront(SLTNode** pphead)
{
	assert(pphead);
	assert(*pphead);

	if ((*pphead)->next == NULL)
	{
		free(*pphead);
		*pphead = NULL;
		return;
	}
	
	SLTNode* next = (*pphead)->next;
	free(*pphead);
	*pphead = next;
}

//SLTNode* SLTFind(SLTNode** pphead, SLTDataType x)
//{
//	assert(pphead);
//	assert(*pphead);
//	SLTNode* pcur = *pphead;
//	while (pcur)
//	{
//		if (pcur->data == x)
//		{
//			return pcur;
//		}
//		pcur = pcur->next;
//	}
//	return NULL;
//}

void SLTInsert(SLTNode** pphead, SLTNode* pos, SLTDataType x)
{
	assert(pphead);
	assert(*pphead);
	assert(pos);

	SLTNode* newnode = SLTBuyNode(x);
	if (*pphead == pos)
	{
		SLTPushFront(pphead, x);
		return;
	}

	SLTNode* pcur = *pphead;
	while (pcur->next != pos)
	{
		pcur = pcur->next;
	}
	newnode->next = pos;
	pcur->next = newnode;
}

void SLTErase(SLTNode** pphead, SLTNode* pos)
{
	assert(pphead);
	assert(*pphead);
	assert(pos);
	if (*pphead == pos)
	{
		SLTPopFront(pphead);
		return;
	}
	SLTNode* pcur = *pphead;
	while (pcur->next != pos)
	{
		pcur = pcur->next;
	}
	pcur->next = pos->next;
	free(pos);
	pos = NULL;
}

void SLTInsertAfter(SLTNode* pos, SLTDataType x)
{
	assert(pos);

	SLTNode* newnode = SLTBuyNode(x);

	newnode->next = pos->next;
	pos->next = newnode;
}

void SLTEraseAfter(SLTNode* pos)
{
	assert(pos);
	SLTNode* del = pos->next;

	pos->next = del->next;
	free(del);
	del = NULL;
}

void SListDesTroy(SLTNode** pphead)
{
	assert(pphead);
	assert(*pphead);

	SLTNode* pcur = *pphead;
	while (pcur)
	{
		SLTNode* next = pcur->next;
		free(pcur);
		pcur = next;
	}
	*pphead = NULL;
}